Early fire detection is important to the safety of occupants in a building. In particular, fire detection allows for building occupants to evacuate the building and first responders to be summoned.
Fire sensors are installed in buildings to provide fire detection. Fire sensors can be installed as standalone devices. Alternatively, fire sensors can be part of an emergency system, which includes a control panel and a data network that connects the control panel to the fire sensors.
One type of fire sensor is a heat fire sensor which detects fire by measuring the ambient temperature. Heat fire sensors can trigger an alarm when the ambient temperature exceeds a threshold temperature and/or when the rate of temperature rise is indicative of fire.
Heat fire sensors comprise a number of components. Their electronics are typically located within a housing. A sensor element, such as a thermistor sensor element or other temperature sensor element, usually projects from the housing. Finally, a sensor guard is often used to protect the sensor element from mechanical impact.
Another type of fire sensor is a smoke fire sensor that detects fire by measuring smoke. Two common technologies for measuring smoke are optical detection and ionization detection.
Both ionization and optical smoke fire sensors comprise a number of components. Both types of fire sensors include housings. Ionization smoke fire sensors include an ionization chamber sensor element in which the smoke is measured, whereas optical smoke fire sensors have an optical chamber sensor element. In both sensors, a sensor guard is often used to protect the chamber sensor elements from mechanical impact.